Patent application title: DISHWASHER WITH AN ALARM DEVICE

Abstract:

A dishwasher (1) (30) having a box-shaped casing (2) having an inner wash
chamber (3) communicating externally through an opening (4) formed in one
of the lateral walls of the casing (2); and at least one dish rack basket
(6) housed inside the wash chamber (3) to house dishes/cutlery within a
hold volume (7) bounded by two predetermined boundary planes (A, B); the
dishwasher (1) having an alarm device (9) which generates, inside the
wash chamber (3), at least one light beam in a direction coplanar with a
reference plane (R) lying in one of the predetermined boundary planes (A,
B); and the alarm device (9) alerting the user to incorrect positioning
of the dishes/cutlery inside the basket (6) when the light beam is
interrupted by the dishes/cutlery.

Claims:

1. A dishwasher comprising:a box-shaped casing having an inner wash
chamber communicating externally through an opening formed in one of the
lateral walls of said casing;at least one dish rack basket housed inside
said wash chamber to house dishes/cutlery within a hold volume bounded by
two predetermined boundary planes; andan alarm device which generates at
least one light beam in a direction coplanar with a reference plane lying
in one of said predetermined boundary planes, said alarm device alerting
the user to incorrect positioning of the dishes/cutlery inside said
basket when said light beam is interrupted by the dishes/cutlery in said
reference plane.

2. A dishwasher as claimed in claim 1, wherein the two predetermined
boundary planes of each hold volume are substantially horizontal and
parallel.

3. A dishwasher as claimed in claim 1, wherein said alarm device comprises
a light-emitting device located on an inner wall of the wash chamber to
project at least one light beam, inside said wash chamber, in a
projection direction coplanar with said reference plane.

4. A dishwasher as claimed in claim 1, wherein said alarm device comprises
a light-emitting device to project at least one light beam, and optical
reflecting/refracting means located on the casing, which receive the
light beam emitted by said light-emitting device to vary the angle of
incidence of the emitted light beam in such a manner to reflect the
emitted light beam in a direction coplanar with said reference plane.

5. A dishwasher as claimed in claim 1, wherein said alarm device comprises
a light-emitting device located on the casing outside of the wash chamber
on one side of the access opening to wash chamber to project the light
beam outside of the wash chamber in a projection direction coplanar with
said reference plane.

6. A dishwasher as claimed in claim 3, wherein said light-emitting device
emits said at least one light beam in a projection direction
substantially crosswise to the direction in which said basket is inserted
into and withdrawn from said wash chamber.

7. A dishwasher as claimed in claim 3, wherein said light-emitting device
comprises at least one LED.

8. A dishwasher as claimed in claim 7, wherein said LED emits at least one
LASER beam.

9. A dishwasher as claimed in claim 3, wherein said alarm device comprises
a detecting unit which detects interruption of said at least one light
beam in said reference plane, and generates an alarm signal indicating
incorrect positioning of the dishes/cutlery in the basket upon detecting
interruption of said at least one light beam.

10. A dishwasher as claimed in claim 3, wherein said detecting unit is
located in said wash chamber.

11. A dishwasher as claimed in claim 9, wherein said detecting unit is
located outside of the wash chamber on one side of the access opening to
wash chamber.

12. A dishwasher as claimed in claim 10, wherein said detecting unit
comprises at least one light-detecting device located on a lateral wall
of the wash chamber to receive said at least one light beam emitted by
said light-emitting device, and to generate said alarm signal when said
light beam is not received.

13. A dishwasher as claimed in claim 9, wherein said detecting unit
comprises visual and/or acoustic indicating means, which receive said
alarm signal from said light-detecting device to generate a
visual/acoustic message informing the user of said incorrect positioning
of said dishes/cutlery in the relative basket.

14. A dishwasher as claimed in claim 3, wherein said light-emitting device
emits a number of light beams in parallel directions lying in said
reference plane.

15. A dishwasher as claimed in claim 6, wherein said light-emitting device
emits a number of light beams in different predetermined directions lying
in said reference plane.

16. A dishwasher as claimed in claim 3, wherein said light-emitting device
comprises actuating means for angularly and continuously varying the
direction of said at least one light beam emitted by the light-emitting
device in said reference plane, so as to sweep the reference plane with
said light beam.

17. A dishwasher as claimed in claim 7, wherein said light-emitting device
comprises at least one support module for supporting said LED; and a
connecting member which connects the support module of the LED to an
inner wall of the wash chamber, and is designed to allow the support
module to move freely with respect to a point connecting said connecting
member to the inner wall.

18. A dishwasher as claimed in claim 17, wherein said alarm device
comprises at least one reference element fixed to an inner wall of said
wash chamber at a predetermined point of incidence of the light beam;
said predetermined point of incidence corresponding to incidence of the
light beam on said wall when the dishwasher is positioned correctly on
the floor.

19. A dishwasher as claimed in claim 18, wherein said detecting device
comprises at least one photoreceiver located on the inner wall of said
wash chamber at said predetermined point of incidence; said detecting
unit, upon non-reception of the light beam by said at least one
photoreceiver, generating an alarm signal indicating improper support of
the dishwasher on the floor.

20. A dishwasher as claimed in claim 1, further comprising at least a
rotary wash member located underneath said basket; one of said
predetermined boundary planes of the hold volume being arranged below
said rotary wash member.

21. A dishwasher as claimed in claim 1, further comprising an extractable
drawer having a wash tub, which houses said dish rack basket and has an
upper opening; said extractable drawer being slidably mounted within said
wash chamber.

22. A dishwasher as claimed in claim 21, wherein said light-emitting
device of said alarm device is fixed on an inner wall of said wash
chamber to project at least one light beam on one boundary plane placed
above said upper opening of said extractable drawer.

23. A dishwasher as claimed in claim 21, wherein said light-emitting
device is fixed on an inner wall of said wash chamber by means of a
support element, and is placed on the inside of said wash tub to project
at least one light beam on a boundary plane placed inside of said wash
tub.

24. A dishwasher as claimed in claim 22, comprising a water-tight vertical
front door which abuts a lateral wall of said casing to seal the access
opening to said wash chamber.

25. A dishwasher as claimed in claim 21, wherein said light-emitting
device is fixed on an inner wall of said wash tub to project at least one
light beam on a boundary plane placed inside of said wash tub.

26. A dishwasher as claimed in claim 25, wherein said wash camber
comprises an upper lid sealing said wash tub of the extractable drawer.

27. A dishwasher as claimed in claim 9, wherein said detecting unit is
located in said wash tub.

Description:

TECHNICAL FIELD

[0001]The present invention relates to a dishwasher with an alarm device.

[0002]More specifically, the present invention relates to a dishwasher
with an alarm device for warning the user of incorrect positioning of
dishes/cutlery inside the dish rack basket; to which the following
description refers purely by way of example.

BACKGROUND ART

[0003]As is known, in currently marketed household dishwashers, incorrect
positioning of dishes and/or cutlery inside the dish rack basket may
result in interference with the rotary wash members mounted inside the
wash chamber of the dishwasher, thus resulting in jamming of the rotary
wash members and possible damage to the dishes or cutlery inside the
basket.

[0004]The inconvenience of the above situation is further compounded by
interference between the dishes/cutlery and the rotary wash members
preventing correct performance of the wash cycle.

[0005]In which case, the user is forced to stop the wash cycle, pull the
basket out of the wash chamber, and position the dishes and/or cutlery
properly.

[0006]Interference as described above also occurs when the basket is
loaded with dishes or cutlery over and above the predetermined size. In
which case, when inserting the basket inside the wash chamber, the dishes
or cutlery may be damaged by collision with the rotary wash members, and
may knock the basket out of position on the respective runners. In which
case, obviously, the door may be prevented from watertight closing the
wash chamber, thus resulting in leakage of the wash chamber with obvious
inconvenience to the user.

DISCLOSURE OF INVENTION

[0007]It is an object of the present invention to provide a dishwasher
with an alarm device for warning the user of incorrect positioning of the
dishes/cutlery inside the dish rack baskets of the dishwasher.

[0008]According to the present invention, there is provided a dishwasher
with an alarm device as claimed in the accompanying Claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]A non-limiting embodiment of the present invention will be described
by way of example with reference to the accompanying drawings, in which:

[0010]FIG. 1 shows a schematic view in perspective, with parts enlarged
for clarity, of a dishwasher with an alarm device in accordance with the
teachings of the present invention;

[0011]FIG. 2 shows a schematic front view, with parts removed for clarity,
of the dishwasher with an alarm device in accordance with the teachings
of the present invention;

[0012]FIGS. 3, 4 and 5 show schematic views in perspective, with parts
removed for clarity, of the dishwasher comprising an alarm device in
accordance with respective alternative embodiments of the present
invention;

[0013]FIG. 6 shows a schematic view in perspective, with parts removed for
clarity, of the dishwasher comprising an alarm device in accordance with
an alternative embodiment of the present invention;

[0014]FIG. 7 shows a schematic front view of a portion of the FIG. 6
dishwasher in two different on-floor positions;

[0015]FIG. 8 shows a schematic front view of the dishwasher comprising an
alarm device in accordance with one possible embodiment of the present
invention;

[0016]FIG. 9 shows a schematic front view of the dishwasher comprising an
alarm device in accordance with a further embodiment of the present
invention;

[0017]FIG. 10 shows schematic front view with parts removed for clarity of
the drawer dishwasher comprising an alarm device in accordance with a
further embodiment of the present invention;

[0018]FIG. 11 shows schematic front view with parts removed for clarity of
the drawer dishwasher comprising an alarm device in accordance with a
further embodiment of the present invention;

[0019]FIG. 12 shows schematic front view with parts removed for clarity of
the drawer dishwasher comprising an alarm device in accordance with a
further embodiment of the present invention;

[0020]FIGS. 13 and 14 show a schematic lateral view with parts removed for
clarity, of the drawer dishwasher of FIG. 11 wherein drawer is in two
different positions;

[0021]FIGS. 15 and 16 show a schematic lateral view with parts removed for
clarity, of the drawer dishwasher of FIG. 12 wherein drawer is in two
different positions;

[0022]FIGS. 17-20 show schematic top views with parts removed for clarity,
of the drawer of the dishwasher of FIG. 12 in accordance with four
different embodiments of the present invention; and

[0023]FIG. 21 shows a schematic front view with parts removed for clarity
of a portion of the drawer dishwasher of FIG. 11 in accordance with a
further embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

[0024]Number 1 in FIG. 1 indicates as a whole a dishwasher comprising: a
box-shaped, preferably, though not necessarily, parallelepiped-shaped
outer casing 2 having an inner wash chamber 3 communicating with the
outside through an opening 4 formed in one of the vertical lateral walls
of casing 2; and a door 5 hinged to casing 2, on one side of the access
opening to wash chamber 3, to rotate, about a preferably, though not
necessarily, horizontal axis of rotation, to and from a closed position
resting on the lateral wall of casing 2 to seal the access opening to
wash chamber 3.

[0025]Dishwasher 1 also comprises one or more dish rack baskets 6 housed
one over the other inside wash chamber 3 and resting on known runners
(not shown) by which to pull the baskets out drawer-fashion through
access opening 4 to wash chamber 3.

[0026]Each basket 6 has a predetermined, preferably parallelepiped-shaped
hold volume 7 (shown by the dotted line in FIGS. 1 and 2), the outer
walls of which define a predetermined space in which to house
dishes/cutlery. In other words, hold volume 7 defines a predetermined
space, within which dishes/cutlery must be housed when positioned
correctly, and which is therefore sized to prevent the dishes/cutlery in
basket 6 from interfering with other parts or baskets of dishwasher 1.

[0027]Hold volume 7 of each basket 6 is bounded at the top and bottom by
two parallel, horizontal boundary planes A and B; and intersection of at
least one of the two boundary planes A and B by a dish/item of cutlery
represents incorrect positioning of the dishes/cutlery inside relative
basket 6.

[0028]Dishwasher 1 also comprises at least two rotary spray wash members 8
mounted for rotation inside wash chamber 3 and having a number of nozzles
designed to direct pressurized-water jets onto the two baskets 6 housed
inside wash chamber 3.

[0029]More specifically, in the FIGS. 1 and 2 example, the top rotary wash
member 8 is located underneath the top basket 6 and an appropriate
distance from boundary plane A of hold volume 7 of the bottom basket 6;
and the bottom rotary wash member 8 is located underneath bottom basket 6
and an appropriate distance from boundary plane B of hold volume 7 of
bottom basket 6.

[0030]Dishwasher 1 also comprises an alarm device 9 for generating,
preferably, though not necessarily inside wash chamber 3, at least one
light beam along a reference plane R lying in either one of boundary
planes A and B, and for alerting the user to incorrect positioning of the
dishes/cutlery inside basket 6 when the light beam is interrupted by the
dishes/cutlery. In other words, alarm device 9 generates at least one
light beam in a direction lying in reference plane R, and alerts the user
to incorrect positioning of the dishes/cutlery inside basket 6 when a
portion of the dishes/cutlery projects beyond reference plane R, thus
interrupting the light beam (FIG. 2).

[0031]In the FIGS. 1 and 2 example, alarm device 9 comprises a
light-emitting device 10 fixed firmly to an inner lateral wall 11 of wash
chamber 3 and having a spot light source which emits a light beam along
reference plane R, which, in the example shown, lies in boundary plane A
of bottom basket 6. Obviously, as inferred above, reference plane R may
alternatively lie in either one of boundary planes B of baskets 6, or in
boundary plane A of top basket 6, and alarm device 9 may comprise an
emitting device 10 for each boundary plane A and B of each basket 6.

[0032]More specifically, in FIG. 1, light-emitting device 10 is fixed
firmly to the outer peripheral edge of wash chamber 3 facing opening 4,
and is located above bottom basket 6 and preferably crosswise with
respect to the direction I in which basket 6 is inserted into and
withdrawn from wash chamber 3.

[0033]Obviously the light-emitting device 10 may alternatively be located
on the casing 2 outside of the wash chamber 3 on one side of the access
opening to wash chamber 3, to project the light beam outside of the wash
chamber 3 in a direction coplanar with reference plane R and crosswise
with respect to the direction I in which basket 6 is inserted into and
withdrawn from wash chamber 3.

[0035]With reference to FIGS. 1 and 2, emitting device 10 comprises at
least one LED 12 or any other similar spot light source capable of
generating collimated light of a frequency preferably, though not
necessarily, in the visible spectrum, e.g. a coloured light clearly
visible by the user.

[0036]Convergence of the light beam emitted by LED 12 may be achieved, for
example, by means of an optical module 13 having a lens and fitted to a
support module 14 of LED 12 to position the lens facing LED 12 and so
ensure generation of a collimated light beam corresponding, for example,
to a LASER beam.

[0037]To better indicate incorrect positioning of the dishes/cutlery
inside basket 6, the number of light beams emitted by emitting device 10
may be increased to cover more of reference plane R.

[0038]FIGS. 3 and 4 show two embodiments of alarm device 9, in which
emitting device 10 generates a number of (in the examples shown, four)
separate light beams in straight directions across wash chamber 3, so as
to intercept any dishes/cutlery projecting beyond reference plane R.

[0040]In the embodiment shown schematically in FIG. 4, an emitting device
10 comprises a number of LEDs 12 oriented to emit respective light beams
along reference plane R in different directions so as to cross wash
chamber 3 at different points.

[0042]In a further embodiment, alarm device 9 is designed to continuously
and angularly vary the direction of the light beam emitted by emitting
device 10. More specifically, in the FIG. 5 example, alarm device 9
comprises a device 15 for continuously varying the angle at which the
light beam is emitted by LED 12 along reference plane R, so as to sweep
reference plane R and indicate incorrect positioning of the
dishes/cutlery upon the dishes/cutlery being intercepted by the sweeping
light beam.

[0043]More specifically, device 15 controls the direction in which the
light beam is emitted by LED 12 so that the angle α between the
emission direction and vertical inner lateral wall 11 ranges between a
first substantially zero angle α1, in which the beam direction
is parallel to lateral wall 11 and coplanar with reference plane R, and a
final angle α2, e.g. of 90°, in which the direction of
the light beam is substantially perpendicular to lateral wall 11 and
coplanar with reference plane R.

[0044]More specifically, in the FIG. 5 example, device 15 comprises an
actuating device, e.g. an electric drive unit connected mechanically in
known manner to support module 14 of LED 12 to rotate the support module
about a longitudinal axis L, of emitting device 10, perpendicular to
reference plane R and coplanar with lateral wall 11.

[0045]In the example shown, emitting device 10 may be housed in a seat 16
formed in lateral wall 11, and device 15 may be connected to the top wall
of seat 16 to support and rotate LED support module 14.

[0046]In an alternative embodiment (not shown), device 15 comprises an
optical reflecting system having a number of movable mirrors, which
receive the beam emitted by LED 12, and are rotated about longitudinal
axis L of emitting device 10 to vary the angle of incidence of the light
beam on the mirrors and, hence, the direction of the light beam inside
wash chamber 3, in the same way as shown in FIG. 5.

[0047]In a further embodiment shown in FIG. 6, emitting device 10 is
housed inside seat 16 formed in lateral wall 11, and, in addition to
support module 14 supporting LED 12, also comprises a connecting member
17, which may be defined by a spherical joint or a supporting arm
connecting support module 14 to the top wall of seat 16 at a connecting
point P, and allows support module 14 to oscillate freely in any
direction with respect to connecting point P.

[0048]In the FIGS. 6 and 7 example, emitting device 10 also comprises a
weight 18 preferably fixed firmly to the underside of support module 14
to keep emitting device 10 positioned, by force of gravity, with its
longitudinal axis L coaxial with a vertical reference axis V, regardless
of the position of casing 2 of dishwasher 1.

[0049]Emitting device 10 therefore oscillates freely with respect to
connecting point P, so that its longitudinal axis L is coaxial with
vertical reference axis V, and the direction/s of the light beam/s
generated by emitting device 10 are always perfectly horizontal,
regardless of the position in which dishwasher 1 rests on the floor.

[0050]With reference to FIGS. 6 and 7, alarm device 9 also comprises at
least two reference elements 19 fixed to the inner walls of wash chamber
3 at two points, each corresponding with a condition in which dishwasher
1 is supported correctly on the floor. More specifically, each reference
element 19 corresponds with a point of incidence of a light beam on a
respective wall when dishwasher 1 is supported correctly, i.e.
substantially horizontally, on the floor.

[0051]In actual use, when the point of incidence of one of the light beams
emitted by emitting device 10 fails to coincide with a corresponding
reference element 19, the user is alerted that dishwasher 1 is not
supported correctly on the floor.

[0053]Improper support of dishwasher 1 may obviously also be indicated by
rotating a light beam about longitudinal axis L and in reference plane R,
and determining whether or not the trajectory defined by the points of
incidence of the light beam on the walls of wash chamber 3 intersects
both reference elements 19.

[0054]Reference elements 19 may comprise stickers or any other visible
marks fixed to/formed on lateral walls 22 and 23 at the points of
incidence of the light beams corresponding to correct on-floor support of
dishwasher 1.

[0055]In a further embodiment, in addition to emitting device 10, alarm
device 9 also comprises a detecting unit 20, which detects interruption
of the light beam emitted by emitting device 10 preferably, though not
necessarily inside wash chamber 3, and generates an alarm signal
indicating incorrect positioning of the dishes/cutlery inside basket 6.

[0056]With reference to FIG. 8, detecting unit 20 substantially comprises
a detecting device 21 fitted to lateral wall 23 of wash chamber 3 to
receive the light beam/s emitted by emitting device 10, and to generate
an alarm signal on detecting the absence of at least one of the
predetermined light beams, caused by interruption of the light beam by
the dishes/cutlery.

[0057]More specifically, detecting device 21 may comprise one or more
photoreceiving devices 26, e.g. photodiodes, each for receiving a light
beam emitted by a corresponding LED 12. More specifically, in the FIG. 8
example, in which emitting device 10 comprises only one LED 12, detecting
device 21 is fixed firmly to the wall 23 of wash chamber 3 facing wall 11
fitted with LED 12, and is located at the point of incidence of the light
beam emitted by the LED. Obviously, in the event emitting device 10
comprises a number of LEDs 12, detecting device 21 comprises a number of
photodiodes, each fitted to lateral wall 23 and aligned with the
corresponding LED 12 to receive the relative light beam.

[0059]More specifically, indicator device 25 may comprise an acoustic
and/or visual indicator module defined, for example, by a LED, or by a
display for displaying a message indicating incorrect positioning of the
dishes/cutlery inside basket 6; and electronic unit 24 may be defined by
a signal processing circuit or a microprocessor connected to detecting
device 21 to receive the alarm signal and determine incorrect positioning
of the dishes/cutlery. Electronic unit 24 is also connected to indicator
device 25 to activate the visual/acoustic message on determining
incorrect positioning of the dishes/cutlery.

[0060]In connection with the above, it should be pointed out that
dishwasher 1 in accordance with the FIGS. 6 and 7 embodiment, i.e. with
emitting device 10 fixed to the wall of casing 2 to oscillate about point
P, may be equipped with detecting unit 20 to determine not only incorrect
positioning of the dishes/cutlery inside basket 6, but also improper
support of dishwasher 1 on floor S.

[0061]More specifically, as shown in FIG. 9, detecting device 21 may be
located at reference element 19 to receive the light beam emitted by
relative emitting device 10, and, if the light beam is not received, to
generate the alarm signal indicating improper support on floor S.

[0062]When installing the dishwasher, in fact, non-reception of the light
beam by detecting device 21 (FIG. 9) means the light beam impinges on a
point of wall 23 other than reference element 19, thus indicating
improper support of dishwasher 1 on floor S. In which case, electronic
unit 24, by means of indicating device 25, informs the user by generating
a visual/acoustic message indicating improper support of dishwasher 1.

[0063]In connection with the above, it should be pointed out that, in the
embodiments described employing detecting unit 20, emitting device 10 may
comprise LEDs 12 for emitting light beams with a frequency range in the
non-visible spectrum.

[0064]In actual use, when installing dishwasher 1, detecting unit 20
generates the alarm signal on detecting the absence of a light beam from
emitting device 10; and electronic unit 24, by means of indicator device
25, indicates improper support of dishwasher 1 on the floor.

[0065]Alarm device 9 of dishwasher 1, as described above, has the major
advantage of enabling the user to determine practically immediately
incorrect positioning of the dishes/cutlery in basket 6, thus reducing
the risk of damage to the dishes/cutlery and, at the same time,
preventing jamming of the rotary wash members, thus ensuring correct
performance of the wash cycle.

[0066]Moreover, provision of detecting device 21 at reference element 19
provides, when installing dishwasher 1, for automatically indicating
improper support of dishwasher 1 on the floor.

[0067]Clearly, changes may be made to the dishwasher and alarm device as
described and illustrated herein without, however, departing from the
scope of the present invention as defined in the accompanying Claims.

[0068]More specifically, in an alternative embodiment (not shown), the
detecting device 21 may be located on the casing 2 outside of the wash
chamber 3 on one side of the access opening to wash chamber 3 to receive
the light beam emitted by relative emitting device 10 located outside of
the wash chamber 3.

[0069]In addition, the hold volume 7 of the top basket 6 may have
dimensions to contain also the rotary spray wash member 8 arranged below
of the basket 6. With reference to example shown in FIG. 10, hold volume
7 of top basket 6 is bounded at the bottom by the horizontal plane B
which is located below the spray wash members 8 of the top basket 6. In
this case, the light-emitting device 10 of the alarm device 9 is fixed to
the lateral wall 11 of wash chamber 3 and emits the light beam along the
reference plane R, which lies in boundary plane B of top basket 6 below
the rotary spray wash member 8.

[0070]Of course it should be point out that hold volume 7 of bottom basket
6 could be bounded at the top by the horizontal plane A which is located
shortly below the spray wash members 8 of the top basket 6. In this case,
the light-emitting device 10 of the alarm device 9 is fixed to the
lateral wall 11 of wash chamber 3 and emits the light beam along the
reference plane R, which lies in boundary plane A of bottom basket 6
shortly below of rotary spray wash member 8 of top basket 6.

[0071]In addition, alarm device 9 of front-loading domestic dishwasher 1
described above could be used in a "drawer dishwasher", (FIGS. 11-21)
which is a known dishwasher 1 having one or a number of modular
extractable dishwasher unit stacked preferably, though not necessarily
one above the other forming part of a furniture.

[0072]For example, the embodiments shown into FIGS. 11 and 12 relate to
drawer dishwashers 30 which are similar to front-loading domestic
dishwasher 1 and in which their components are numbered, where possible,
with the same reference numbers of identical components of dishwasher 1.

[0073]With reference to examples shown in FIGS. 11 and 12, wash chamber 3
of the drawer dishwasher 30 comprises a wash tub 31 which is embodied as
an extractable drawer 32 to house the dish rack 6 and supporting
dishes/cutlery.

[0074]In detail, the extractable drawer 32 is slidably mounted within wash
chamber 3 on known support runners (not shown) to move between a first
position (shown in FIG. 13 or 15), wherein extractable drawer 32 is
entirely on the inside of wash chamber 3 to enable dish/cutlery washing
cycle, and a second position (shown in FIG. 14 or 16), wherein
extractable drawer 32 is pulled out of wash chamber 3 to enable the user
to place dishes and/or cutlery properly inside of the wash tub 31.

[0075]With reference to examples shown in FIGS. 11 and 12, the extractable
drawer 32 comprises a front wall 31a, a bottom wall 31b and opposite side
walls 31c that collectively define the wash tub 31. In a manner also
known in the state of the art, wash tub 31 of the extractable drawer 32
has a upper opening 34 to enable the user to place dishes and/or cutlery
properly inside of wash tub 31.

[0076]The extractable drawer 32 has a predetermined, preferably
parallelepiped-shaped hold volume 7 (shown by the dotted line in FIGS.
11-16), the outer walls of which define a predetermined space in which to
house dishes/cutlery. In other words, hold volume 7 defines a
predetermined space, within which dishes/cutlery must be housed when
positioned correctly, and which is therefore sized to prevent the
dishes/cutlery from interfering with the outer peripheral edge of wash
chamber 3 when user put drawer 32 into wash chamber 3.

[0077]In a manner known in the state of the art, drawer dishwasher 30 also
comprises a known washing system 33 which is mounted on the extractable
drawer 32 to wash the dishes and/or cutlery inside of wash tub 31 when
extractable drawer 32 is placed completely inside of wash chamber 3 on
its first position. In detail, in the example shown in FIGS. 11 and 12
washing system 33 comprises known pneumatic devices (not shown) and/or
pump motor (not shown) and a rotary spray wash member 8 mounted for
rotation inside of wash tub 31 and having a number of nozzles designed to
direct pressurized-water jets onto the rack baskets 6 housed inside wash
tub 31 of drawer 32. More specifically, in the FIGS. 11 and 12 example,
rotary wash member 8 of washing system 33 is located underneath rack
basket 6 and an appropriate distance from boundary plane B of hold volume
7.

[0078]With reference to the embodiment shown in FIGS. 11, 13 and 14,
drawer dishwasher 30 also comprises a water-tight vertical front door 35
which is fitted to the front wall 31a of wash tub 31 of extractable
drawer 32 and preferably, though not necessarily incorporates a drawer
pull 36. When fully closed in the first position, water-tight vertical
front door 35 abuts the lateral wall of casing 2 to seal the access
opening 4 to wash chamber 3.

[0079]With reference to FIGS. 11, 13 and 14, alarm device 9 of drawer
dishwasher 30 generates, preferably, though not necessarily inside wash
chamber 3, at least one light beam along a reference plane R lying
boundary plane A and for alerting the user to incorrect positioning of
the dishes/cutlery inside wash tub 31 when the light beam is interrupted
by the dishes/cutlery.

[0080]In other words, alarm device 9 of drawer dishwasher 30 generates at
least one light beam in a direction lying in reference plane R, and
alerts the user to incorrect positioning of the dishes/cutlery inside
wash tub 31 when a portion of the dishes/cutlery projects beyond
reference plane R, thus interrupting the light beam.

[0081]In the FIGS. 11, 13 and 14 example, the light-emitting device 10 of
alarm device 9 is fixed firmly to an inner lateral wall 11 of wash
chamber 3 and has a spot light source which emits a light beam along
reference plane R, which, in the example shown, lies in boundary plane A.

[0082]More specifically, in FIGS. 11, 13 and 14, light-emitting device 10
is fixed firmly to the outer peripheral edge of wash chamber 3 facing
opening 4, and is located above the upper rim of the extractable drawer
32 and preferably crosswise with respect to the direction I in which
extractable drawer 32 is inserted into and withdrawn from wash chamber 3.

[0083]Obviously the light-emitting device 10 may alternatively be located
on the casing 2 outside of the wash chamber 3 on one side of the access
opening 4 to wash chamber 3 (not shown), to project the light beam
outside of the wash chamber 3 in a direction coplanar with reference
plane R and crosswise with respect to the direction I in which drawer 32
is inserted into and withdrawn from wash chamber 3.

[0085]Obviously the alarm device 9 of the drawer dishwasher 30 may
alternatively be similar to the alternative embodiments shown in FIGS. 3
and 4, in which emitting device 10 generates a number of separate light
beams in straight directions across wash chamber 3.

[0086]In addition, the alarm device 9 of the drawer dishwasher 30 may
alternatively be similar to the alternative embodiment shown in FIG. 5
wherein, alarm device 9 is designed to continuously and angularly vary
the direction of the light beam emitted by emitting device 10.

[0087]Furthermore, the alarm device 9 of the drawer dishwasher 30 may
alternatively be similar to the alternative embodiment shown in FIG. 6,
wherein emitting device 10 is housed inside seat 16 formed in lateral
wall 11, and, in addition to support module 14 supporting LED 12, also
comprises a connecting member 17, which may be defined by a spherical
joint or a supporting arm connecting support module 14 to the top wall of
seat 16 at a connecting point P, and allows support module 14 to
oscillate freely in any direction with respect to connecting point P.

[0088]In addition, the alarm device 9 of the drawer dishwasher 30 may
alternatively be similar to the alternative embodiment shown in FIG. 6
wherein emitting device 10 is positioned, by force of gravity, with its
longitudinal axis L coaxial with a vertical reference axis V, regardless
of the position of casing 2 of dishwasher.

[0089]In addition, the alarm device 9 of the drawer dishwasher 30 may
alternatively be similar to the alternative embodiment shown in FIG. 8 or
9 wherein alarm device 9 also comprises a detecting unit 20, which
detects interruption of the light beam emitted by emitting device 10
inside wash chamber 3 and generates an alarm signal indicating incorrect
positioning of the dishes/cutlery inside wash tub 31.

[0090]In an alternative embodiment shown in FIG. 21, alarm device 9 is
fixed firmly to the inner lateral wall 11 of wash chamber 3 by and its
light-emitting device 10 is placed at least partially inside of the wash
tub 31 of the extractable drawer 32 to emit a light beam along reference
plane R, which, in the example shown, lies in boundary plane A located
under the upper rim of the upper opening of the drawer 32. In detail in
the example shown in FIG. 21, alarm device 9 comprises a L-shaped support
element 9a having an end fixed to the inner lateral wall 11 of wash
chamber 3, and the other end which is located under the upper rim of the
upper opening of the drawer 32 to support the light-emitting device 10
inside of the wash tub 31.

[0091]FIGS. 12, 15 and 16 show a different embodiment of drawer dishwasher
30 which comprises a door 41 fitted to the front wall 31a of wash tub 32,
whereas the washing chamber 13 comprises an upper lid 42 sealing the wash
tub 31 when extractable drawer 32 is inserted into washing chamber 3. In
a manner also known in the state of the art, lid 42 is able to enter into
a water-tight sealing cooperation with the drawer's upper opening 34 upon
pushing the drawer 32 into the washing chamber 3.

[0092]With reference to FIGS. 12, 15 and 17, the light-emitting device 10
of alarm device 9 is fixed firmly to a wall of the wash tub 31 and has a
spot light source emitting a light beam along reference plane R, which,
in the example shown, lies in the boundary plane A.

[0093]More specifically, in FIGS. 15, 16 and 17, light-emitting device 10
is placed in an angle between to side walls below the upper rim of the
extractable drawer 32 to project the light beam in such a manner to cover
an angle β of about 90° so as to cover reference plane R.

[0094]In detail light-emitting device 10 emits a light blame lying in
reference plane R and indicating incorrect positioning of the
dishes/cutlery upon the dishes/cutlery being intercepted by the light
blame.

[0095]With reference to an embodiment shown in FIG. 18 light-emitting
device 10 is placed in a side wall below the upper rim of the extractable
drawer 32 to project the light beam in such a manner to cover an angle of
about 180° so as to generate a light blame which covers the
reference plane R.

[0096]With reference to an embodiment shown in FIG. 19 the alarm device 9
of the drawer dishwasher 30 may alternatively be similar to the
alternative embodiment shown in FIGS. 3 and 4, and the emitting device 10
could generate a number of separate light beams in straight directions
across the wash tub 31.

[0097]Of course it should be point out that the alarm device 9 shown in
FIG. 19 could comprise at least a detecting unit 20, which detects
interruption of the light beam emitted by emitting device 10 inside of
wash tub 31 of drawer 32, and generates an alarm signal indicating
incorrect positioning of the dishes/cutlery inside basket 6. In detail
with reference to FIG. 20, detecting unit 20 comprise one or more
photoreceiving devices 26, e.g. photodiodes, each for receiving a light
beam emitted by a corresponding emitting device 10 to generate an alarm
signal on detecting the absence of at least one of the predetermined
light beams, caused by interruption of the light beam by the
dishes/cutlery.

[0098]Of course it should be point out that the outer casing 2 of the dish
washer 1 or of the drawer dishwasher 30 may have any kind of outer shape,
i.e. a rounded shape.

[0099]In addition, it should be point out that the lateral wall comprising
the opening 4 of the inner wash chamber 3 may be the top wall of the
casing 2. In other words the opening 4 of the inner wash chamber 3 could
be an upper opening and may be formed in the top wall of the casing 2.

[0100]In an alternative embodiment (not shown), alarm device 19 comprises
an optical reflecting/refracting system having one or more reflecting or
refracting devices (not shown), which receive the light beam emitted by
LED 12, and are located into the wash chamber 3 or into the wash tub 31
of the drawer to vary the angle of incidence of the emitted light beam in
such a manner to reflect the emitted light beam in a direction coplanar
with reference plane R. More specifically the beam emitted by LED 12 is
not coplanar with the reference plane R and is reflected by optical
reflecting/refracting system in the direction coplanar with reference
plane R. Obviously alarm device 19 alerts the user to incorrect
positioning of the dishes/cutlery inside basket 6 when the reflected
light beam is interrupted by the dishes/cutlery.